[Free Registration/Login Required] XtraMath is an excellent site for students to practice their basic number facts and develop automatic recall. Teachers can register for a free account and are then guided through the steps for setting up a class of students, after which they receive a list of logins for students. The site is set up for use at home or at school. A nice feature is that the site is designed so that it can be used as a supplemental activity in the classroom where a student does a set of exercises for up to ten minutes, then the screen alerts the student to call another student in the class for their turn.